This invention relates to wet shaving systems using blade cartridges, and particularly to razor handles adapted for engaging blade cartridges that are pivotable about their major axis during shaving.
Most wet shaving systems available today use blade cartridges rather than blades alone as the replaceable elements of the system. The cartridges allow precise location and orientation of the blade in its support structure, and are even more necessary for the use of dual blade systems, where two cutting edges are located in a cartridge in a precise relationship.
A variety of techniques is used for attaching cartridges to razor handles. One popular technique utilizes a dovetail coupling arrangement between the handle and cartridge to fix the cartridge on the handle at a desired angle. An example of such a system is seen in U.S. Pat. No. 3,783,510 for RAZOR HAVING TANDEMLY MOUNTED BLADES BONDED IN A DISPOSABLE CARTRIDGE issued to Dawidowicz et al. Furthermore, some techniques include the significant addition of attaching the cartridge to the handle in a way that allows the cartridge to pivot in a controlled way, about its major axis. Pivotal attachment of the cartridge allows the blade mounted in the cartridge to follow skin surface contours independently of the handle orientation. The cartridge is pivotable between limits and ordinarily is biased toward a preferred neutral angular position vis-a-vis the handle. Furthermore, a portion of the cartridge ordinarily has a camming surface that is adapted to meet a cam follower on the handle when the cartridge is attached. For example, Nissen et al (U.S. Pat. No. 4,083,104) shows a reusable razor system in which a pivotable blade cartridge with a camming surface is engaged by a spring-biased cam follower forming part of the razor handle. The camming surface and cam follower coact to urge the cartridge to or toward its neutral position.
In yet another example, U.S. Ser. No. 108,741 for ONE-PIECE RAZOR HANDLE FOR PIVOTABLE CARTRIDGE filed Dec. 31, 1979, by the present applicant, there is disclosed a simple one-piece plastic razor handle for mounting a pivotable cartridge. A cantilevered cam follower formed integrally with the handle acts to urge the blade cartridge to its neutral position. This entire combination may be disposable if no provision is made for disengaging the cartridge from the razor handle after it is used. On the other hand, the one-piece handle may be formed such that by squeezing the handle the mounting jaws resiliently open to receive or release a pivotable cartridge, thereby affording at least some reusability of the system. This latter arrangement is disclosed in U.S. Ser. No. 108,742 for ONE-PIECE RAZOR HANDLE filed Dec. 31, 1979, by the present applicant.
Recently, certain blade cartridges have been provided with a dovetail type coupling structure for fixed mounting to an appropriate handle and a pivot-type coupling structure for pivotal mounting to another appropriate handle. An example of such a cartridge is found in U.S. Design Ser. No. 946,389 for SAFETY RAZOR CARTRIDGE WITH CLEAN-OUT DEVICE filed Sept. 27, 1978, by Evan N. Chen, and marketed under the trade name SCHICK.RTM. Ultrex II.
While the pivotable razor system offers certain contour-following advantages during shaving, there are situations such as the trimming of sideburns, etc., in which the user may prefer to have a fixed razor system. Certain efforts have been made to provide a locking mechanism in pivot-type razor handles such that the pivotable cartridge may be locked in a fixed position. One such arrangement is disclosed in U.S. Pat. No. 3,938,247 for SHAVING SYSTEM WITH PIVOTAL HEAD issued Feb. 17, 1976, to Carbonell et al. This arrangement, and at least one other similar one marketed in Japan by the Feather Safety Razor Company, Ltd., provide relatively complex locking mechanisms which form separate and movable portions of the razor handles. Such locking arrangements may be relatively bulky in appearance and are costly to manufacture and assemble.
Accordingly, it is an object of the invention to provide a razor handle having a simple and inexpensively manufactured means for latching a pivotable cartridge in a fixed position. It is another object to provide a razor handle having such a latch, which latch is releasable so as to selectively return the cartridge to a pivoting mode. It is a further object to provide such latching means on a one-piece razor handle. It is still a further object to provide such latching means in a form particularly suited for use with blade cartridges of the type which may be mounted on either a fixed or a pivot-type razor handle.